The 10mm was made by KWA (TW Version of KSC Japan), and for whatever strange reason KWA decided to not include it in their version. As per a light weight silencer, i've never really come across a feather light silencer and for that exact reason I never usually game with a suppressor attached. The best I can recommend to you are King Arms light weight slim series which are indeed what the name suggests.
Kokanee: I got the G20C slide custom milled by ProG4 to my specs, I paid through the nose for that just to have a one off piece produced. The EKO Cobra slide is made by Prime.
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